$green = #02a774
$yellow = #f5a100
$bc = #e4e4e4
top-border-1px($color)
  position relative
  border none
  &:before
    content ''
    position absolute
    left 0
    top 0
    width 100%
    height 1px
    background-color $color
@media only screen and (-webkit-device-pixel-ratio 2)
  .border-1px
    &::before
      transform scaleY(0.5)
@media only screen and (-webkit-device-pixel-ratio 3)
  .border-1px
    &::before
      transform scaleY(0.33333)
bg-image($url)
  background-image url($url + '@2x.png')
  @media (-webkit-device-pixel-ratio 3), (min-device-pixel-ratio 3)
    background-image url($url + '@3x.png')
clearFix()
  &::after
    content ''
    display block
    clear both